France's President Nicolas Sarkozy has drawn criticism for the expulsion of almost 1,000 Gypsies from France. Photograph: Ho/Reuters

Nicolas Sarkozy has pledged to press ahead with legislation to strip immigrants who attack police of their French nationality. The French president rowed back, however, from imposing a similar punishment on those who practise polygamy or female genital mutilation.

As much of France returned to work after the summer holidays, Sarkozy made his first major statement of the new political term after meeting ministers responsible for security, justice and immigration.

He reiterated his determination to implement the sanctions, which he first threatened after three days of riots in the southern city of Grenoble which were sparked when police shot dead a suspected armed robber in July.

The Elysée Palace said the president would implement the measures "as soon as possible". The punishment would apply to foreign-born criminals who had obtained French nationality in the last 10 years and who "endanger the life of a person in charge of public security, in particular the police and gendarmes".

The proposals have been vehemently criticised by the opposition and some legal experts who say they are contrary to the constitution that states all French citizens are equal before the law regardless of race, creed or origin.

Gerard Larcher, president of the Senate upper house of parliament, told Le Monde: "The real question is: would it really improve French people's security?"

Critics accuse Sarkozy, who also faces international criticism over the expulsion of almost 1,000 Roma last month, of playing to extreme rightwing voters by linking violent crime and immigration.

Besson, 52, a former socialist who defected to Sarkozy's ruling right-of-centre UMP party, had planned to marry Tunisian-born art student Yasmine Tordjam, 24, at the town hall in the chic 7th arrondissement of Paris – where former justice minister Rachida Dati is mayor – on September 16.

When more than 1,000 Facebook users had signed up to the group Create Havoc at Eric Besson's Marriage, the divorced father of three told France 5 television he was changing the date and place "so it will go back to what it should be – an exclusively private matter".

"There should be a Chinese wall between public matters and private matters and this wall is being breached," Besson said adding that he did not want his children, his new wife or his ex-wife to be "collateral damage for my political choices".

"I'm not afraid of it turning rowdy or havoc being created. However as I'm a minister this requires security measures and I have no desire to get married in this context with security guards.

"I don't see why public funds should be spent on guaranteeing the security of a marriage that is in the private domain."

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